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Biomedical subjects

R A Lopes

Publications and source records attributed to R A Lopes.

At least 55 records · Page 3Linked to original sources
PubMed1987

The cephalic glands of Brazilian reptilia and amphibia. IV. Histology of labial, premaxillary, and Duvernoy's glands in the colubrid snake Oxyrhopus trigeminus.

A study of the morphology of the salivary glands of the colubrid snake Oxyrhopus trigeminus showed the following: The acini of supralabial, infralabial, and premaxillary glands are formed by mucous and mucoserous cells; the tubules of Duvernoy's gland are formed by seromucous cells; and mucous cells produce neutral and acid mucosubstances, mucoserous cells secrete neutral and acid mucosubstances and protein, and seromucous cells have neutral mucosubstance and protein secretions.

Animals↗
PubMed1986

Morphological and morphometric study of the alterations on young mouse parotid gland with subpatent Chagas' disease.

In the present study we describe the morphological and morphometric alterations induced by two Trypanosoma cruzi strains (strains Y and Bolivia) in the mouse parotid gland during the subpatent period of infection. The acinar cells of animals inoculated 27 d after birth showed reduced eosinophilia, greater chromatin condensation, reduced height, and basally dislocated nucleus. The area occupied by the acini was decreased (999.38 micron 2 to 546.76 micron 2) and the volume of the acinar cells was reduced (116.28 micron 3 to 63.28 micron 3). Reduced height (21.20 micron to 14.28 micron) and decreased nuclear volume (125.28 micron 3 to 77.28 micron 3) occurred in the striated ducts. In the excretory duct there was reduced nuclear volume (121.16 micron 3 to 76.14 micron 3) and decreased height of the epithelial cells (26.05 micron to 14.00 micron). The presence of lymphoplasmocyte infiltrates was also observed. The changes induced by the Bolivia strain were qualitatively similar to those induced by strain Y, but more severe in nature. The present results indicate that infection with T. cruzi induces delayed development of the mouse parotid gland during the subpatent phase.

Animals↗
PubMed1984

Changes in sodium and potassium excretion and urinary volume in rats submitted to hypervitaminosis A.

Hypervitaminosis A induces the following changes in rat kidney: decrease in sodium and potassium excretion and an increase of urinary volume. In order to determine the possible reversibility of these alterations, the authors allowed the hypervitaminotic animal to recover for 30 and 60 days. After a 30-day recovery period for urinary volume, a 20-day recovery period for sodium excretion, and a 10-day recovery period for potassium excretion, the alterations were reverted to normal.

Animals↗
PubMed1983

The gallbladder of the Capivara Hydrochoerus hydrochoeris (Mammalia: Rodentia).

The authors studied morphological and histochemically the mucopolysaccharides and proteins in the gallbladder tubular glands and epithelial cells of the capivara Hydrochoerus hydrochoeris. Based on the results the authors concluded: 1. the gallbladder single columnar epithelium consists of secretory, migrating, and goblet cells; 2. in the lamina propria are single coiled tubular glands; 3. goblet and tubular gland cells show neutral and sulphated mucopolysaccharides and sialic acid; 4. columnar cells show neutral mucopolysaccharides and protein radicals; 5. migrating cells show only protein radicals.

Animals↗
PubMed1983

Rhythm of development in the oocyte of the tilapia Oreochromis niloticus L. (Pisces: Cichlidae); a morphometric and histochemical study.

The ovary of the tilapia Oreochromis niloticus was studied morphologically and morphometrically; the zonas granulosa and radiata, the ooplasm and the yolk globules were studied histochemically. The ovary is of typical teleostean type consisting of a wall and developing oocytes. The development of oocytes has been divided into 10 cytological stages. Histochemically the zona radiata and yolk globules contain glycoprotein (neutral mucopolysaccharides and protein radicals alpha-amino groups, cystine, cystein, tyrosin, tryptophane, and arginine. The zona granulosa and ooplasm contain neutral and carboxylate acid mucopolysaccharides and protein radicals alpha-amino group, cystein, cystine, tyrosin, arginine, and tryptophane.

Animals↗
PubMed1982

Morphometric study of malformations induced by hypervitaminosis A on rat fetus Meckel cartilage, maxillary bone and mandible.

Morphological and histological studies were carried out to determine the effects on fetal development in rats of a single intraperitoneal injection of 150,000 I.U. of vitamin A, given to the mothers on the 10th day of gestation. The Meckel cartilage of malformed animals appeared to be diminished, with larger nuclei, less numerous isogenous nests, smaller cellular and thin perichondrium and more abundant cartilaginous matrix, which was less deeply stained by alcian blue. The maxillary bone and mandible of the treated fetuses showed thin and poorly calcified trabeculae, smaller medullary spaces and a less fibrous, and more cellular periosteum. These data were confirmed with morphometric techniques.

Abnormalities, Drug-Induced↗
PubMed1982

The salivary glands of Ameiva ameiva (Teiidae, Lacertilia). A morphological, morphometric and histochemical study.

The authors studied morphological, morphometric, and histochemically the mucosubstances and proteins in the salivary glands of the lizard Ameiva. Based on the results, the authors concluded: 1. The labial salivary gland is formed by small mucous and mucoserous glands; the sublingual gland by mucoserous cells. 2. Mucous cells show neutral and sulphated mucosubstances and sialic acid. Mucoserous cells of the labial gland show neutral mucosubstance, sialic acid, hyaluronic acid and protein radicals. Mucoserous cells of the sublingual gland show neutral mucosubstance, sialic acid and protein radicals. 3. The average values for acinar area were: 1,198.11 microns 2 for mucoserous acini and 2,105.95 microns 2 for mucous acini of the labial salivary gland. The average values for nucleus volume were: 47.41 microns 3 for mucoserous cells and 38.97 microns 4 for mucous cells. 4. The average values for acinar area and nuclear volume of the mucoserous cells of the subingual gland were respectively: 1,474.62 microns 2 and 67.77 microns 3.

Animals↗
PubMed1982

[The salivary glands of Philodryas patagoniensis Girard, 1857 (Serpentes, Colubridae). A morphological, morphometric and histological study].

Morphological, morphometrical and histochemical studies of the cell types in the salivary glands of Philodryas patagoniensis have been performed. It is concluded: 1) the acini of supra, infralabial and premaxillary glands are formed by mucous and mucoserous cells; the Duvernoy's gland by seromucous cells; 2) mucous cells show neutral and sulphated mucosubstances and sialic acid; mucoserous cells show neutral mucosubstance, sialic acid and protein radicals; seromucous cells of Duvernoy's gland show neutral mucosubstance and protein radicals. The acinar area, height of tubule and duct cells, and nuclear volume of acinar, tubule and duct cells were evaluated morphometrically.

Animals↗
PubMed1981

[Femur development during lactation in rats whose mothers had undergone vitamin A treatment on the 10th day of gestation. Morphologic and morphometric study].

Administration of a single dose of vitamin A (0.20 ml of Arovit, Roche, containing 30,000 IU of vitamin A palmitate), injected intraperitoneally in rats on the 10th day of gestation had the following effects on the femur of the newborn rats during lactation: longer femurs; earlier appearance of the epiphysial centers; a lower number of cells, increased matrix and consequent earlier maturation process for the zone of hypertrophic cartilage, and thicker and more numerous bone trabeculae. These data were confirmed by morphometric techniques.

Animals↗
PubMed1980

Myxoma of oral soft tissue.

The clinical and histopathologic characteristics of oral soft tissue myxoma are reviewed. A case of soft tissue myxoma of the alveolar ridge is presented, and the diagnosis is discussed.

Adult↗
PubMed1980

Angiolipoma of the cheek.

The clinical and histopathologic characteristics of oral lipoma are reviewed. A rare case of angiolipoma of the cheek is presented, and the histopathology of this tumor is discussed.

Adult↗
PubMed1980

Morphometric study of the effects of insulin on the rat submandibular gland.

After administration of an overdose of insulin, the following effects on the rat submandibular gland were observed: increased gland weight and acinar cell size, with increased cytoplasmic acidophilia and a larger number of secretory granules. The granular ducts showed higher cells and increased nuclear volume. The above data were confirmed by morphometric techniques. The total protein values for the submandibular gland were higher in rats 30 and 60 minutes after insulin overdose, when compared with those for control rats. Administration of an overdose of insulin caused a lowering of the glycemic level during the entire experimental period.

Animals↗
PubMed1980

Morphometric study of the reversibility of thyroid alterations in rats submitted to hypervitaminosis A.

Administration of excess vitamin A doses to rats causes atrophy of the thyroid, with smaller follicles, more abundant cytoplasm, less colloid and decreased nuclear volume. The connective tissue were more abundant. In order to determine the possible reversibility of these alterations, the authors allowed the hypervitaminotic animals to recover for 30 days. After the recovery period, the glandular lesions were reversed to normal. These data were confirmed with morphometric technique.

Animals↗
PubMed1979

Effect of hypervitaminosis A on tongue muscles of the rat. A morphometric study.

Daily administration of 200 I.U. vitamin A/gram body weight to rats, for a period of 10 days, causes generalized hypertrophy of the tongue muscles. The data were confirmed with morphometric techniques, consisting of increased cytoplasm and decreased nuclei and empty spaces, obtained by the Chalkley technique, nuclei of similar volume, obtained with the use of karyometry, and larger areas of cross-sections of muscle fibers.

Animals↗